Table 3. Variation in Forage Mineral Content for Native Grasses from TX and Mixed Grass Hay from AR  and NRC Requirements for Dry and Lactating Beef Cows (adapted from Herd, 1997; Davis et al., 1999)

 

 

Mineral

 

 

Average

 

Range of Analyses

Requirements, (NRC,1996)

Dry Cow  Lactating Cow

Texas

 (Native Grass)

  Calcium, %

  Phosphorus, %

  Magnesium, %

  Potassium, %

  Sulfur, %

  Iron, ppm

 Copper, ppm

  Manganese, ppm

  Zinc, ppm

Arkansas

(Mixed Grass Hay)

  Calcium, %

  Phosphorus,%

  Magnesium,%

  Potassium, %

  Sulfur, %

  Iron, ppm

  Copper, ppm

  Manganese, ppm

  Zinc, ppm

 

 

.48

.10

.12

.91

.13

205

5

50

21

 

 

.59

.29

.26

1.85

.22

231

10.2

197

24.3

 

 

.29-.67

.04-.16

.07-.17

.28-1.54

.07-.19

43-367

3-7

25-75

13-29

 

 

.23-1.35

.11-.66

.13-.47

.61-5.03

.12-.44

56-3982

1.1-27.6

38-1125

15.4-184.5

 

 

      .25                .31

      .16                .21

      .12                .20

      .60                .70

      .15                .15

       50                 50

       10                 10

       40                 40

       30                 30